I have happened to notice something of late (using ~amd64). I have doc set in my make.conf. I have noticed that at times build will fail. And when I try again using USE="-doc", the build will complete.

Given this builds additional documentation, I will be removing it. I found it interesting that what seemed to me like an innocuous option, can actually be quite problematic._________________Desktop
Debian Sid 64-bit
Gentoo 64-bit (amd64)